The invention relates to connections of a wheel bearing unit to the brake caliper carrier and to the wheel carrier for a wheel of a motor vehicle.
Many publications concern the integration of parts in the area surrounding a wheel bearing. Thus, mounting openings for the brake caliper carrier, which are arranged on the stationary part of the wheel bearing unit, are shown in DE 84 01 811 U. This arrangement has a problem in that different wheel bearing units have to be produced for the left-hand and right-hand sides of the vehicle to enable attachment of the brake caliper carrier in an identical position. Although a wheel bearing unit which can be used on both sides of the vehicle is shown in FIG. 2 of this publication, an additional part is required in this Figure for mounting the brake caliper.
A wheel bearing unit having mounting openings for accommodating a brake caliper carrier on the stationary flange of the wheel bearing unit is shown in DE 101 05 298. The problem with this arrangement in FIG. 7b is that the radial distances shown there between the mounting openings for the wheel carrier and the mounting openings for the brake caliper carrier are too small in order to be able to firmly screw the brake caliper in place, without causing strength problems in the wheel carrier. Recesses have to be made in the wheel carrier around the mounting openings of the brake caliper carrier. These recesses affect the strength of the wheel carrier. If the distance as shown in FIG. 7b is too small, strength problems occur in the wheel carrier. In the case of driven wheels additionally, further free space for the constant velocity joint is to be provided inside the wheel carrier.
The same problems also apply to the arrangement in DE-A 21 05 123 wherein the mounting openings for the brake caliper carrier are arranged on the same pitch circle as the mounting openings for the wheel carrier.
The object of the invention is to provide a wheel bearing unit which has mounting openings for accommodating a brake caliper or brake caliper carrier and which can be used on both sides of a vehicle, while also providing a favorable stress distribution due to adequate strength in the material of the adjacent portion of the wheel carrier or spindle.
This object is achieved by the invention. The invention comprises mounting openings arranged symmetrically in the stationary ring of the wheel bearing unit. If all the openings lie symmetrically relative to at least one axis of symmetry, the wheel bearing unit can be used on both the left-hand and the right-hand vehicle side. Positioning the mounting openings for the brake caliper assembly on a larger pitch circle enables the wheel carrier to be designed with a continuous annular region for accommodating the wheel bearing unit and enables recesses for mounting the brake caliper carrier to lie outside this annular region. This is especially important for driven wheels, since the constant velocity joint in the case of these wheels is arranged inside the wheel bearing unit, and this region therefore has to be recessed inside the wheel carrier.
Providing the mounting openings to lie in one plane has production advantages.
The ends of the mounting opening for accommodating the brake caliper assembly and for mounting the bearing may be coplanar, or the brake caliper mounting openings may be axially offset outwardly (i.e., away from the spindle) by locating the mounting openings for the brake caliper assembly in an angled projection. The advantage of the mounting opening being axially offset is that the recesses in the wheel carrier can be dispensed with, since the brake caliper carrier lies between the wheel carrier and the angled projection.
Other features and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawings.